[PATCH AUTOSEL 6.11 117/244] pmdomain: core: Use dev_name() instead of kobject_get_path() in debugfs

Sasha Levin
2024-09-25T11:42:20Z

From: Ulf Hansson <ulf.hansson@linaro.org>

[ Upstream commit 9094e53ff5c86ebe372ad3960c3216c9817a1a04 ]

Using kobject_get_path() means a dynamic memory allocation gets done, which
doesn't work on a PREEMPT_RT based configuration while holding genpd's raw
spinlock.

To fix the problem, let's convert into using the simpler dev_name(). This
means the information about the path doesn't get presented in debugfs, but
hopefully this shouldn't be an issue.

Signed-off-by: Ulf Hansson <ulf.hansson@linaro.org>
Tested-by: Raghavendra Kakarla <quic_rkakarla@quicinc.com> # qcm6490 with PREEMPT_RT set
Acked-by: Sebastian Andrzej Siewior <bigeasy@linutronix.de>
Link: https://lore.kernel.org/r/20240527142557.321610-4-ulf.hansson@linaro.org
Signed-off-by: Sasha Levin <sashal@kernel.org>
---
drivers/pmdomain/core.c | 23 +++--------------------
1 file changed, 3 insertions(+), 20 deletions(-)

diff --git a/drivers/pmdomain/core.c b/drivers/pmdomain/core.c
index 7b2f8b1417de8..17b31a524697a 100644
--- a/drivers/pmdomain/core.c
+++ b/drivers/pmdomain/core.c
@@ -3210,7 +3210,6 @@ static int genpd_summary_one(struct seq_file *s,
[GENPD_STATE_OFF] = "off"
};
struct pm_domain_data *pm_data;
- const char *kobj_path;
struct gpd_link *link;
char state[16];
int ret;
@@ -3243,17 +3242,10 @@ static int genpd_summary_one(struct seq_file *s,
}

list_for_each_entry(pm_data, &genpd->dev_list, list_node) {
- kobj_path = kobject_get_path(&pm_data->dev->kobj,
- genpd_is_irq_safe(genpd) ?
- GFP_ATOMIC : GFP_KERNEL);
- if (kobj_path == NULL)
- continue;
-
- seq_printf(s, "\n %-50s ", kobj_path);
+ seq_printf(s, "\n %-50s ", dev_name(pm_data->dev));
rtpm_status_str(s, pm_data->dev);
perf_status_str(s, pm_data->dev);
mode_status_str(s, pm_data->dev);
- kfree(kobj_path);
}

seq_puts(s, "\n");
@@ -3422,23 +3414,14 @@ static int devices_show(struct seq_file *s, void *data)
{
struct generic_pm_domain *genpd = s->private;
struct pm_domain_data *pm_data;
- const char *kobj_path;
int ret = 0;

ret = genpd_lock_interruptible(genpd);
if (ret)
return -ERESTARTSYS;

- list_for_each_entry(pm_data, &genpd->dev_list, list_node) {
- kobj_path = kobject_get_path(&pm_data->dev->kobj,
- genpd_is_irq_safe(genpd) ?
- GFP_ATOMIC : GFP_KERNEL);
- if (kobj_path == NULL)
- continue;
-
- seq_printf(s, "%s\n", kobj_path);
- kfree(kobj_path);
- }
+ list_for_each_entry(pm_data, &genpd->dev_list, list_node)
+ seq_printf(s, "%s\n", dev_name(pm_data->dev));

genpd_unlock(genpd);
return ret;
--
2.43.0